|
Habitat requirements for the bittern
Based on the RSPB assessments the following appears to be necessary for successful
breeding of bitterns in the UK:
- Freshwater reedbeds for breeding, 20-25 ha though areas >40 ha appear
to be necessary if more than one pair is to be accommodated;
- Bittern require abundant fish stocks. They hunt along the reed/open water
interface in shallow water in reedbeds;
- Network of dykes and pools >20% and at least 600 m of reed edge per hectare;
- Water depth fluctuating between 10 and 25 cm summer and winter levels;
- Good water quality;
- Little or no saline intrusion*.
| Guidance: When creating
or managing
reedbeds the above requirements will help to inform the methods
of habitat restoration or re-creation that are adopted. |
Caveat: *Bitterns may feed at the edge of tidal areas, especially
on eels which require freshwater/saltwater transition when migrating. Creating
artificial barriers can have unforeseen consequences as was the case at Titchwell
in North Norfolk. Here the ability of eels to cross sea walls was impaired by
sea wall erected to control water regimes for bird conservation, resulting in
their being smaller numbers available in the bittern feeding areas.
|
